Some vehicles are designed to travel on surfaces covered with snow and/or ice. These vehicles, for instance snowmobiles, often have at least one ski at the front. Most of them have two spaced-apart front skis. Skis are working much better than wheels on snow or ice-covered surfaces. However, on a surface that is not covered with snow or ice, they are not. Vehicles with skis are often very difficult to steer on hard or relatively hard surfaces such paved roads or the like. Thus, whenever possible, drivers of vehicles with skis avoid travelling outside surfaces covered with snow and/or ice. When this is not possible, they minimize the travel distance and speed on these other surfaces.
Many vehicles are designed to travel on paved roads using wheels. Automobiles are examples of such vehicles. They offer a level of comfort that is not found in the vast majority of the vehicles designed for snow-covered and/or ice-covered surfaces.
Converting a road vehicle having wheels into a vehicle with skis at the front was done in the past. However, replacing some of the wheels of a vehicle with skis essentially confines the converted vehicles to snow-covered and/or ice-covered surfaces, just like other vehicles designed for such surfaces.
Some arrangements have been suggested in the past where the driver of a vehicle can select between using either a ski or a wheel, depending on where the vehicle is. Wheel-ski systems are devices where both skis and wheels are available to the driver. Yet, wheel-ski systems have also been suggested for use on airplanes. See for instance U.S. Pat. No. 2,106,934 (Saulnier) of 1938. Other wheel-ski systems have been suggested for use on snowmobiles. See for instance U.S. Patent Publication 2006/0151983 (Despres) of 2006.
While the general idea of using wheel-ski systems on vehicles have resulted in a number of different constructions, none has been found completely satisfactory and accordingly, room for improvements still exists in this technical field.